Question Front or top mounted radiator + push/pull vs push-pull?

[bumblebee953]

Getting a little confused on where best to mount rads for an AIO cooling solution.

Front-mounting:

My understanding is that a typical front mounted rad would have the fans out front - push config. The rad would get blasted with fresh cool air. If mounted behind the rad in pull config, it won't be as ideal at blasting cool air but would help get air into the rest of the case better.
And push-pull would kinda get the best out of both worlds. But the trade-off of front mounting would mean that the cool air would've passed through the rad and be a little warmer, and so the rest of the case like the GPU isn't cooled as well. So better CPU cooling, worse GPU cooling.
Another point to consider is that a more front-restricted case (e.g. Phanteks Evolv X) would suffer a bit more having the rad in front because vs just pure intake fans, already restricted airflow has to pass through yet another barrier - the rad. Perhaps a better case in this config would be one with unblocked front mesh? e.g. Fractal Meshify S2

Top-mounting:

Pretty much the opposite cost/benefit of front mounting. Maybe the restrictive nature of the case front design won't matter as much here. But the cool air that comes in from pure front intake fans would've passed through the GPU before it reaches the top rad, resulting in less cooled CPU? A push-pull would probably help again in this case; not at getting more cool air, but at least would help exhausting the warm air out of the rad a bit quicker. But a lot of cases won't have as much room between the top of the motherboard and the top case vents. I do see top-mounted rads as the more popular config though.


Is this the right understanding of tradeoffs?

 

[CountMike]

Getting a little confused on where best to mount rads for an AIO cooling solution.

Front-mounting:

My understanding is that a typical front mounted rad would have the fans out front - push config. The rad would get blasted with fresh cool air. If mounted behind the rad in pull config, it won't be as ideal at blasting cool air but would help get air into the rest of the case better.
And push-pull would kinda get the best out of both worlds. But the trade-off of front mounting would mean that the cool air would've passed through the rad and be a little warmer, and so the rest of the case like the GPU isn't cooled as well. So better CPU cooling, worse GPU cooling.
Another point to consider is that a more front-restricted case (e.g. Phanteks Evolv X) would suffer a bit more having the rad in front because vs just pure intake fans, already restricted airflow has to pass through yet another barrier - the rad. Perhaps a better case in this config would be one with unblocked front mesh? e.g. Fractal Meshify S2

Top-mounting:

Pretty much the opposite cost/benefit of front mounting. Maybe the restrictive nature of the case front design won't matter as much here. But the cool air that comes in from pure front intake fans would've passed through the GPU before it reaches the top rad, resulting in less cooled CPU? A push-pull would probably help again in this case; not at getting more cool air, but at least would help exhausting the warm air out of the rad a bit quicker. But a lot of cases won't have as much room between the top of the motherboard and the top case vents. I do see top-mounted rads as the more popular config though.


Is this the right understanding of tradeoffs?

With radiator, push or pull makes no difference, same amount of air goes thru because it's closed on all sides and has no air leakage.

 

[madmatt30]

Radiator positioning really is dependant on case and components.
Some scenarios front intake makes more sense, other scenarios top exhaust is better.

Your tradeoff description is generally correct apart from fan placement (push/pull) which may make 1 or 2% difference max as CountMike has already stated.

It all depends what needs cooling more in all honesty.

If running something like an i9 or a ryzen 9 which run obscenely hot anyway and a mid range gpu or something with a very robust cooling system front intake would generally be better.

With something like a 6c/12t ryzen or a lesser intel which are easier to keep cool and a high end power hungry gpu a top exhaust would probably make more sense.

As said completely case/component dependant which dictates the best option.

 

[bumblebee953]

With radiator, push or pull makes no difference, same amount of air goes thru because it's closed on all sides and has no air leakage.

How about push pull? Is it worth it to sandwich the rad? And again I guess it's more suitable when rad is front mounted because a lot of cases don't have much room on the top and the giant sandwich may block the top of the motherboard or have to worry about RAM clearance.

If I do push pull, do the fans on either side have to match, in both size and RPM? I ask because some cases come with fans that I don't want because I'd rather use fans I already own, but I can use those extra included fans towards a push pull config, but they may not match.

e.g. 360mm AIO with included 3x 120mm fans. But I have 2x 140mm fans. Can I still stick the 140s on the other side of the rad, leaving 80mm of room on that side? What if they're different RPMs and CFMs? High static pressure vs high airflow? Or do I actually want them different?

 

[bumblebee953]

It all depends what needs cooling more in all honesty.

If running something like an i9 or a ryzen 9 which run obscenely hot anyway and a mid range gpu or something with a very robust cooling system front intake would generally be better.

With something like a 6c/12t ryzen or a lesser intel which are easier to keep cool and a high end power hungry gpu a top exhaust would probably make more sense.

As said completely case/component dependant which dictates the best option.

I am planning on getting an i7 10700K and a 3080. Both run pretty hot I think? Though I probably would give the edge to 3080... I guess in that case I should prioritize GPU cooling and go with top-mounting?

 

[alexbirdie]

I do have:

corsair carbide 678c , a 3950x and a 2080S.

Front : 2 radiators intake
read: 1 radiator blowing out.
top: radiator for 360 aio with 3 fans getting air from inside the case and blowing it outside through the rad.

-----> very good temperature for CPU, GPU, VRM , chipset and ram even on hot days with room-temps about 30 degree.

 

[bumblebee953]

I do have:

corsair carbide 678c , a 3950x and a 2080S.

Front : 2 radiators intake
read: 1 radiator blowing out.
top: radiator for 360 aio with 3 fans getting air from inside the case and blowing it outside through the rad.

-----> very good temperature for CPU, GPU, VRM , chipset and ram even on hot days with room-temps about 30 degree.

Ahh you have a full water cool solution. I guess I was asking more from only CPU AIO point of view.

 

[alexbirdie]

Ahh you have a full water cool solution. I guess I was asking more from only CPU AIO point of view.

No.

I have only a AIO for CPU (Thermaltake 360 water 3.0 sync argb).

 

[bumblebee953]

No.

I have only a AIO for CPU (Thermaltake 360 water 3.0 sync argb).

You said you have 2 rads on the front and 1 rad in the rear? Or do you mean fans?